Companion Planting & Botanical Pesticides: Concepts & Resources

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Sustainable Agriculture A program of the National Center for Appropriate Technology • 1-800-346-9140 • www.attra.ncat.org Companion Planting & Botanical Pesticides: Concepts & Resources

By George Kuepper Certain plants can benefit others when planted in close proximity or used as botanical pesticides. This and Mardi Dodson publication discusses the scientific and traditional basis for companion planting associations including Published July 2001 trap cropping, weed suppression, physical-spatial interactions, and other relationships. It provides a Updated April 2016 companion planting chart for common herbs, vegetables, and flowers, as well as a listing of literature by Justin Duncan, resources. An appendix provides information on the Three Sisters, a traditional Native American com- NCAT Agriculture panion planting practice. Specialist ©NCAT Traditional IP125 Companion Contents Planting Traditional Companion ompanion planting Planting ...... 1 can be described as Companion Planting Chart...... 2 establishing two or Cmore plant species in close The Scientific Foundations for proximity for some cul- Companion Planting...... 3 tural benefit (such as pest Botanical Pesticides...... 8 control or higher yield). Options for System The concept embraces a Design...... 10 number of strategies that References...... 11 increase the biodiversity of Further Resources...... 13 agroecosystems (Cunning- Appendix: Ancient ham, 1998). Companions...... 15 Generally, companion Buckwheat (left) suppresses weeds and attracts beneficial insects that can help planting is thought of as protect brassicas (right). Photo: Andy Pressman, NCAT This material is based upon work that is supported by a small-scale gardening the National Institute of practice. However, here the term is applied in its made around the middle of the 20th century, were Food and Agriculture, U.S. broadest sense to include applications to commer- based on the results of sensitive crystallization Department of Agriculture, cial horticultural and agronomic crops. ATTRA tests (Philbrick and Gregg, 1966). under award number 2013- has another publication, Intercropping Principles 51106-20970. A step beyond companion planting is using botan- and Production Practices, that provides additional ically based pesticides. Companion planting is a ATTRA (www.attra.ncat.org) information on larger-scale applications. is a program of the National passive approach, while botanical sprays are more Center for Appropriate Technology Although companion planting has a long history, intensive. Both rely on phytochemicals in the host (NCAT). The program is funded through a cooperative agreement the mechanisms of beneficial plant interaction plant being different from the companion plant, with the United States Department have not always been well understood. Traditional or the one being treated. One consideration for of Agriculture’s Rural Business- recommendations (see Table 1) used by gardeners using a botanical spray that is different from sim- Cooperative Service. Visit the NCAT website (www.ncat.org) have evolved from an interesting combination of ply planting a companion is that the botanical for more information on historical observation, horticultural science, and spray may affect the host plant’s development our other sustainable a few unconventional sources. For example, some (Tavares et al., 2011). The same can be said of agriculture and energy projects. of the recommendations for companion planting, synthetic pesticides (Spiers et al., 2008). www.attra.ncat.org Page 1 Table 1. COMPANION PLANTING CHART FOR HOME & MARKET GARDENING (compiled from traditional literature on companion planting)

CROP: COMPANIONS: INCOMPATIBLE: Amaranth Corn, Onion, Potato Brassica Artichokes, Cardoon Brassicas, Cucumbers, and Prostrate Cucurbits Potatoes Asparagus Basil, Cilantro, Parsley, Tomato, Comfrey Alliums Basil Most Vegetables Rue Beans Most Vegetables, Herbs, Marigolds Allium, Gladiolus Irish Potato, Cucumber, Corn, Strawberry, Celery, Beans, Bush Allium Summer Savory Allium, Beets, Kohlrabi, Beans, Pole Corn, Marigolds, Summer Savory, Radish Sunflower Beets, Chard Brassicas, Alliums, Lettuce Pole Beans Blackberries Grapes, Tansy Raspberries Blueberries Clover, Strawberries, Yarrow Tomatoes Borage Squash, Strawberries, Tomatoes Allium, Aromatic Herbs, Beets, Celery, Chamomile, Dill, Pole Beans, Cabbage Family (Brassicas) Chard, Clover, Spinach Strawberries, Tomato Carrots, Parsnip Allium, English Pea, Lettuce, Rosemary, Sage, Tomato Dill, Fennel Celery Allium & Brassicas, Bush Beans, Nasturtium, Tomato Beans, Cucumber, English Pea, Irish Potato, Pumpkin, Corn Tomato Squash Beans, Carrots, Corn, Cucumbers, Radishes, Cowpea Garlic, Onions, Potatoes Turnips Beans, Cabbage, Corn, English Pea, Radish, Cucumber Aromatic Herbs, Irish Potato Sunflowers Eggplant Basil, Beans, Catnip, Lemon Grass, Marigold Fennel Nothing Everything Ginger Basil, Tomatoes Gourds Corn, Sunflowers Grapes Basil, Beans, Chives, Clovers, Mustard, Oregano, Peas Cabbage Lettuce Carrot, Cucumber, Radish, Strawberry Melons Amaranth, Beans, Chamomile, Corn Brassicas Onion (Allium) Beets, Brassicas, Carrot, Lettuce, Summer Savory Okra Peppers, Squash, Sweet Potatoes Beans, English Peas Parsley Asparagus, Tomato Pea, English Carrots, Radish, Turnip Allium, Gladiolus, Irish Peanut Eggplant, Melon, Squash, Sunflower Potato Peppers Basil, Clover, Marjoram, Tomato Brassicas Potato, Irish Basil, Beans, Brassicas, Horseradish, Marigolds Cucurbits, Tomato, Pumpkins Corn, Marigold Sunflower, Rosaceae

Page 2 Companion Planting & Botanical Pesticides: Concepts & Resources CROP: COMPANIONS: INCOMPATIBLE: Basil, Beets, Cabbage, Carrots, Corn, Lettuce, Turnips, Purslane Beans, English Peas Radish Radish Cucumber, English Pea, Lettuce, Nasturtium Irish Potato Spinach Celery, Faba Bean, Strawberry Hyssop Squash Nasturtium, Corn, Marigold Strawberries Borage, Bush Beans, Lettuce, Pyrethrum, Caraway Irish Potato Sugarcane English Peas, Cowpeas Sorghum, Johnson Grass Sunflowers Beans, Corn, Cucumber, Melons, Peanuts Potatoes Sweet Potato Okra, Peppers, Sunflowers Sorghum, Johnson Grass Alliums, Asparagus, Basil, Carrot, Cucumber Tomato Pole Beans Marigold, Nasturtium, Nettles, Parsley, Rosemary Irish Potato, Fennel, Turnip, Rutabaga English Pea Cabbage Family Watermelon Nasturtium, Marigold Irish Potato, Mustard Sources: www.gardenzone.info/articles/indexnew.php?article=11 and https://en.wikipedia.org/wiki/List_of_companion_plants#cite_note-passionfruit_infonet-30 Notes: Brassica includes arugula, bok choi, broccoli, Brussels sprouts, cabbage, cauliflower, collards, horseradish, kale, kohlrabi, mizuna, mus- tards, nasturtium, radish, and turnip. Allium includes chives, garlic, leeks, onions, scallions, and shallots.

The Scientific Foundations Dead-End, Perimeter, Semiochemically Assisted, Related ATTRA Biological Control-Assisted and Genetically publications for Companion Planting Modified Trap Cropping (Shelton and Badenes- www.attra.ncat.org Science has routinely provided evidence that sup- Perez, 2006). Trap crops should be as healthy as Intercropping Princi- ports some facets of sustainable agriculture, like possible to ensure their desirability to their tar- companion planting. While the scientists may not ples and Production geted pest species (Mizell et al., 2008). Practices call their work companion planting per se, the results of their work show that there is potential Conventional Trap-Cropping is simply planting Farmscaping to for home gardeners and small farms to capital- a low-value crop that is more attractive to pests Enhance Biological ize on the natures of plants to affect each other’s than the adjacent higher value crop, as in the Control example of the diamondback moth, above. The growth. Whether these plants harbor beneficial Conservation Tillage insects, release nutrients advantageous to another classic and most economically beneficial example crop’s growth, or simply provide a buffer against of this is attracting Lygus bugs away from cotton Mushroom Cultiva- the elements to tender seedlings, the tenets of fields by planting alfalfa nearby (Godfrey and tion and Marketing companion planting have been shown repeatedly Leigh, 1994). The alfalfa must be kept physiologi- through rigorous scientific experimentation to be cally young with repeated mowing in order for beneficial to planting systems. it to remain attractive to Lygus throughout the season. Trap crops are often destroyed as a means Trap cropping of pest control (Hokkanen, 1991). Sequential Trap Cropping Sometimes, a neighboring crop may be selected uses time to sepa- because it is more attractive to pests and serves to rate pests from valuable crops. Escape by time is distract them from the main crop. An excellent already a common practice in sustainable agricul- example of this is the use of collards to draw the ture (Feeny, 1976) so it makes sense that time is diamondback moth away from cabbage (Mitch- also used in trap cropping. Trap crops are planted ell et al., 2000). ahead of the main crop, and the timing of these traps crops can be critical. For example, in one Trap cropping breaks into several sub-categories: study, strawberry seedlings planted alone had a Conventional, Sequential, Multiple, Push-Pull, 43% mortality rate from wireworms, strawberry www.attra.ncat.org Page 3 (Khan et al., 2014). Also known as stimulo-deterrent trap cropping (Miller and Cowles, 1990), this idea represents a revolutionary option for organic and sustainable producers. Not only is it easily adapted, but it also has strong foundations in scientific research. Dead-End Trap Cropping is most useful when positioned to buffer crops from adjacent pest sources, as with other trap-crop techniques (Shel- ton and Badenes-Perez, 2006). In Dead-Ending, the trap crop is attractive to the target pest but the larvae are unable to complete their life cycle on the trap crop. One example is the use of Cro- seedlings planted two weeks before being inter- talaria juncea to attract the pod-boring Maruca cropped with wheat had a 27% mortality rate, and vitrata away from such crops as cowpeas, pigeon strawberry seedlings only had a 5% mortality rate peas, and soybeans and kill 50-100% of their when wheat was planted eight days in advance larvae (Jackai and Singh, 1983). (Vernon et al., 2000). This set-up could also be considered a nurse crop in a sense. Usually nurse Semiochemically Assisted Trap Cropping crops protect from climatic adversity, but in this makes use of pheromones rather than kairomones case the nurse crop is protecting the strawberry (Shelton and Badenes-Perez, 2006). Semiochemi- seedlings from attack by wireworms. cals are chemicals that carry a message, while a kairomone is a semiochemical that may not Multiple Trap Cropping usually involves several benefit its emitter. Plants emit kairomones and different species of crops to maintain attractive- ness to the pest throughout the growth cycle of the crop (Hokkanen, 1989). One such system, recommended by researchers at the University of Florida for controlling stink bugs and leaf-footed bugs, is to grow Triticale, Sorghum, Pennisetum (millet), buckwheat, and sunflowers around the perimeter of the cash crop (Mizell et al., 2008). Push-Pull Trap Cropping combines an attractant border crop with a repellant intercrop to protect crops from pests. The most successful version of this method was developed in Kenya to reduce damage from boring insects in corn. They use a legume, Desmodium, to repel pests (and also fix more than 300 pounds of nitrogen per acre) (Whitney, 1966) and use Pennisetum as an attractant (Pickett et al., 2014). This technology has been adopted by more than 10,000 farmers

Page 4 Companion Planting & Botanical Pesticides: Concepts & Resources insects benefit from them in some way, such as controlled by predators in sorghum plots adjacent using the plant as a food source. Pheromones, on to cotton fields (Tillman and Mullinix, 2004; the other hand, are semiochemicals that affect Virk et al., 2004). members of the same species; e.g., mating semio- Genetically Modified Trap Cropping makes use chemicals from receptive females alerting males of GMO traits to assist in crop protection. Crops to their receptivity. In field applications, these with the Bacillus thuringiensis (Bt) trait can be chemicals can be used to draw pests away from planted earlier than conventional crops to collect the cash crop to be destroyed in the trap crop. For migrating pests that cannot survive the toxins pro- example, one experiment found that an applica- duced by the plants. When the conventional crops tion of Dimethyl Disulfide attracted predators are planted, they will be under much less pest pres- of the cabbage root fly, Delia radicum, resulting sure due to the early generations of the pest popu- in a 60% egg mortality rate (Kergunteuil et al., lation being wiped out by the transgenic trait (Cao 2012). This research also showed potential for et al., 2005). The erosion of Bt trait efficacy may (Z)-3-hexenyl acetate, a kairomone released from lead to reduction in the amount of pests destroyed damaged leaves that encourages pest oviposition, by this method (Tabashnik et al., 2013). For more to be used in trap cropping. From their work, we information on GMO traits, please refer to the can surmise that mechanically bruised crops will ATTRA publication Transgenic Crops. encourage females to deposit their eggs in the damaged area, which could then be sprayed or otherwise destroyed, leaving the main body of the Symbiotic Nitrogen Fixation crop relatively pest-free. The drawbacks of using Legumes—such as peas, beans, and clover— semiochemicals are that they can be expensive have the ability to fix atmospheric nitrogen for and hard to find for specific pests. For example, their own use and for the benefit of neighboring none exist, as of yet, for stinkbug pests (Mizell plants via symbiotic relationships with Rhizobium et al., 2008). Rincon Vitova (www.rinconvitova. and Bradyrhizobium bacteria. One example of com) has semiochemicals for some other pests a crop benefiting from interplanted legumes is available for purchase. that of beans and potatoes. Potatoes are known Biological Control-Assisted Trap Cropping to be heavy nitrogen feeders. In one experiment, (BCATP) combines concepts of farmscaping potatoes were planted with beans (Phaseolus and trap cropping. Trap cropping makes use of vulgaris) or with corn. While the corn, also being the verges of the fields to draw pest populations a heavy feeder, was shown to reduce potato-tuber away from crops. BCATP not only draws the size, beans did the opposite (Manorama and Lal, pests but also their natural enemies. These trap 2010). Similarly, forage legumes are commonly crops also serve as sources of biological controls seeded with grasses to reduce the need for nitro- for adjacent fields, to further reduce pest inci- gen fertilizer. Likewise, fava beans are sometimes dence. One example is cotton bollworms being interplanted with corn. Some research indicates

www.attra.ncat.org Page 5 that this companion-planting duo is beneficial in kills them. This method takes quite a while, but desert reclamation where both nitrogen and phos- over the course of a few cycles, pernicious weeds phorous levels are low (Mei et al., 2012). like Amaranth, nutsedge, and Bermuda grass can be reduced. One must remember that organic Another use for legumes is as a green manure agriculture is an intricate system that utilizes the crop. Green manures are crops that are grown harmonious balances in nature for human benefit. to be killed and then incorporated into the soil, Attempting to pick it apart like a machine may or left as mulch to increase soil organic matter not give the desired results. and, in this case of legumes, nitrogen. A Cana- dian study showed that by incorporating grazing sheep into the rotation, soil nitrogen could Modification of Root-Zone be increased, as well as the animals’ weight-gain Environment (Cicek et al., 2014). Companion plants can act as living mulches. One of our favorite combinations is that of broccoli Weed Suppression and crimson clover. Research in Hawaii showed that this combination increases the amount of One other benefit of legumes and other vining spiders that patrol the broccoli plants to control crops, such as cucurbits, is the suppression of pests (Hooks et al., 2007), but what we value is weeds. A well-known example is the role squash the way the clover protects soil moisture and keeps plays in the Three Sisters Method of growing the soil cooler for the broccoli. In addition to cool- beans, corn, and squash. In this situation, the ing the soil, a companion cover crop can improve squash plants’ prostrate vines form a dense can- other factors—tilth, soil structure, runoff control, opy and smother weed competition. Other com- and water-holding capacity—and also build up panion growing systems have also used corn but soil organic matter (Hartwig and Ammon, 2002; exchanged squash for Desmodium, which has a Folorunso et al., 1992). In gardening situations three-fold role. First, it suppresses Striga, a para- where deciduous trees are nearby, the canopy pro- sitic vine that devastatingly reduces corn yields vides shade for sun-tender vegetables, but more in Africa. Inclusion of a Desmodium compan- importantly the leaf litter adds potassium and ion crop triples corn yield over corn planted in carbon to the soil. The increased organic carbon monocrop. It appears that Striga germination is content in turn increases water-holding capacities suppressed by the presence of Desmodium. Next, and Cationic Exchange Capacity, or CEC. Thus, the Desmodium fixes nitrates for the corn crop, trees contribute to soil carbon sequestration in two which also lowers input needs. Third, the Desmo- ways: first they add carbon through leaf decom- dium is a forage legume that provides producers position and then protect it from volatile decom- with a secondary source of income in the form of position by shading the material, not counting fodder once the corn crop is finished. This system the carbon the trees acquire in growth. If the has but one draw-back: it is highly labor-intensive, tree is a nitrogen-fixing legume, then there is also requiring twice the labor of corn monoculture. In an increase in soil nitrates (Tanga et al., 2014). short, it’s twice the work yet triple the revenue per The presence of either trees or cover crops allows acre (Midega et al., 2014). Another unmentioned mycorrhiza populations to build up in the soil benefit could have been the manipulation of the as well (Augé, 2001). Mychorrhiza are soil fungi root zone to benefit the corn plants. Although that form mutually beneficial associations with Striga is an African problem, U.S. producers can plant roots. They can harvest nutrients for plants adapt the methodology that African producers use and even water in time of drought (Kaya et al., to address similar challenges here. 2003). This is particularly useful in vineyards and In a recent study, researchers failed to find con- orchards (Linderman and Davis, 2001; Schreiner, clusive results as to whether organic produc- 2004). Mychorrhizal colonization can even influ- tion reduced weed seeds through soil microbial ence visits by pollinators (Barber and Soper Gor- action (Ullrich et al., 2011). From our own experi- den, 2014). Mychorrhiza-treated tomatoes showed ences, we have found that in organic production, more total yield and more marketable yield than weed-seed persistence is reduced by cover crops tomatoes without mycorrhiza treatment (Candido in rotation providing a dense canopy when the et al., 2015). Mycorrhiza must have plant roots to weed seeds are germinating. This dense canopy join with, so intercropping cover crops with veg- starves the weed seedlings from light and thus etables or permanent plantings allows a grower to

Page 6 Companion Planting & Botanical Pesticides: Concepts & Resources extend the reach of the mychorrhizal hyphae throughout the garden or farm. For more information on mycorrhiza, consult the ATTRA publication Mush- room Cultivation and Marketing.

Biochemical Pest Suppression As mentioned above, some plants exude chemicals from roots or aerial parts that suppress or repel pests and protect neighboring plants. Certain marigolds, for example, release thiophene—a nematode repellent—making marigold a good companion for a number of gar- volatile Allium semiochemicals. The pest contin- den crops (Marotti et al., 2010). The manufacture ues its search because the scent of the susceptible and release by a plant of certain biochemicals, host plant was ‘masked.’ known as allelochemicals, can negatively impact the growth of other plants. Allelochemicals such Physical Spatial Interactions as juglone—found in black walnut— suppress In one example of such an interaction, tall- the growth of a wide range of other plants, which growing, sun-loving plants may share space with often creates a problem in home horticulture. The lower-growing, shade-tolerant species, resulting means by which this suppression occurs is mitosis in higher total yields from the land. Spatial inter- inhibition, which in turn reduces meristematic action can also yield pest-control benefits. The activity. In short, the juglone acts as a growth diverse canopy resulting when corn is compan- retardant on other plants by interfering with the ion-planted with squash or pumpkins is believed ability of the cells to divide (Babula et al., 2014). by proponents of Three Sisters planting to disori- A positive use of plant allelopathy is the use of ent the adult squash vine borer and protect the mow-killed grain rye as a mulch. The allelochem- vining crop from this damaging pest. In turn, icals that leach from rye residue prevent weed the presence of the prickly squash vines is widely germination but do not harm transplanted toma- believed to discourage raccoons from ravaging the toes, broccoli, or many other vegetables. Rye can sweet corn. Besides the classic corn example, there be flattened with a roller-crimper and crops such is also supporting research that shows that in a as melons can be transplanted into the residue. cowpea-sorghum companion planting, cowpeas In this manner, melon yield is enhanced, weed were protected from the striped bean weevil due pressures are lowered, and the soil is protected by to the physical barrier of the tillering sorghum the rye mulch from both desiccation and erosion (Amoako-Atta, 1983). (Ciaccia et al., 2015). Rye is known to have 16 dif- We often think of the benefits of companion ferent allelopathic chemicals (Schulz et al., 2013) planting as limited to reducing pests, but it can and is considered one of the best crops for weed also be effective in reducing plant diseases. In seed suppression (Jabran et al., 2015). a pea-grain intercrop, Ascochyta blight severity Masking is an offshoot of biochemical pest sup- was significantly reduced although there was no pression. It makes use of volatiles to prevent a pest change in disease development. The grain inter- from attacking its favored host. One such example crop modified the canopy microclimate by mak- is the use of garlic and other Alliums in the garden. ing it less humid, and it also reduced the rain- These have been found to deter the green peach drop splash effect, the means by which the disease aphid (Amarawardana et al., 2007). If the insect spores are spread (Schoeny et al., 2008). Canopy is searching for its host when it encounters a field microclimate can also influence insect develop- with vegetables companion-planted with Alli- ment. Temperature changes due to canopy archi- ums, the pest primarily smells the overpowering tecture caused moths to develop three days faster www.attra.ncat.org Page 7 in a compact canopy versus a more open one help to keep pest populations in check. Preda- (Kührt et al., 2006). More on spatial arrange- tors include ladybird beetles, lacewings, hover ment can be found in the ATTRA publication flies, mantids, robber flies, and non-insects such Intercropping Principles and Practices. as spiders and predatory mites. Parasites include a wide range of fly and wasp species including Nurse Cropping tachinid flies and Trichogramma and ichneumo- Tall or dense-canopied plants may protect more nid wasps. Agroecologists believe that by devel- vulnerable species through shading or by pro- oping systems to include habitats that draw and viding a windbreak. Nurse crops such as oats sustain beneficial insects, the twin objectives of reducing both pest damage and pesticide use can have long been used to help establish alfalfa and be attained. Numerous (552) experiments over a other forages by supplanting the more competi- ten-year period were examined to find whether tive weeds that would otherwise grow in their Farmscaping (also known as environmental engi- place. In many instances, nurse cropping is sim- neering) was an effective method of reducing pest ply another form of physical-spatial interaction. populations. The answer was a resounding yes, It can also be a form of inter-seeding. Our earlier but it was at a cost of production of the main crop example from sequential trap cropping, with the (Letourneau et al., 2011). For detailed informa- strawberries, can also be considered nurse crop- tion on establishing beneficial habitats, request ping. Usually a nurse crop protects from climatic the ATTRA publication Farmscaping to Enhance adversity, but in this case it is protecting the straw- Biological Control berry seedlings from insect predation (Vernon et . al., 2000). Many times, nurse crops are used in association with forages, where a fast-germinat- Security Through Diversity ing grass is used with a slower-growing legume A more general mixing of various crops and vari- (Weller, 2006). eties provides a degree of security to the grower. If pests or adverse conditions reduce or destroy a Beneficial Habitats single crop or cultivar, others remain to produce Beneficial habitats—sometimes called refugia or some level of yield. Furthermore, the simple mix- insectary plantings, farmscaping strips, etc.—are ing of cultivars, as demonstrated with broccoli another type of companion plant interaction that in University of California research, can reduce has drawn considerable attention in recent years aphid infestation in a crop (Daar, 1988). Research (Philips et al., 2014). The benefit is derived when supports the concept that diverse crops add to companion plants provide a desirable environment total biomass yield (Mousavi and Eskandari, for beneficial insects and other arthropods—espe- 2011) and that risk in multi-cropping situations cially those predatory and parasitic species which is inherently lower than in monocultures. This increase can be attributed to a more efficient con- sumption of soil nutrients per unit area (Eskan- dari and Ghanbari, 2009).

Botanical Pesticides The great thing about botanical pesticides is that they can be made at home using common ingre- dients. For example, many gardeners enjoy the beauty and sometimes the flavor of nasturtiums. Others grow them for their insect-repelling properties as a companion plant, but nasturtiums have also been shown to have larvacidal effects on leafminers. A methanol extraction of finely chopped nasturtium leaves caused almost 20% A hedgerow of corn reduction in coffee leaf miners (Alves et al., 2013). (right) and sorghum The same kind of extract from a four-o’clock plant (center) next to a cotton field (left) provides habi- killed 50% of the coffee leaf miners, and extract tat for beneficials. Photo: of high mallow and guinea-hen weed killed 60%! Rex Dufour, NCAT Nasturtium phytochemicals were found to be

Page 8 Companion Planting & Botanical Pesticides: Concepts & Resources more or less abundant depending upon the prepa- have the same exact effectiveness, the ability to ration technique used. For example, using heat make the botanical pesticides at home at your during the extraction lowered the available phy- leisure more than compensates for any variabil- tochemicals. Changing the extraction method ity. You may choose to use a blender or juicer if also affected phytochemical content (Bazylko et possible, but this will also alter the antioxidant al., 2013). Extracted solutions also differed from activity (Pyo et al., 2014). fresh-squeezed juice in amounts of flavonoids and A very common botanical pesticide is neem oil. phenols (Bazylko et al., 2014). Aside from extrac- Neem (Azedirachta indica), a tree in the Melia- tion processes, secondary metabolites in plants ceae, is closely related to the invasive chinaberry can also be influenced by climatic conditions and (Melia azedarach), native to Asia, and has been even UV radiation (Rozema et al., 1997). These introduced to many parts of the world due to its factors can either enhance or detract from a given beneficial properties (Sherley, 2000). The oil is plant’s successful use as a source of a botani- derived from the seeds. Neem has been found to cal pesticide and should be taken into account contain 99 insecticidal phytochemicals including regarding efficacy. While every batch may not the powerful antifeedant azadirachtin. Neem has

Table 2. SELECTED BOTANICAL PESTICIDES CHART FOR HOME & USE (adapted from Prakesh and Rao) Ageratum Ageratochromene true bugs, beetles, moths, fruitflies, grasshoppers Agave saponines repels rice weevils, kills mosquito larvae, termites Aesculus Aesclin bean and Japanese beetles, termites Ajuga Ajugarin armyworms, bollworms Allium Diallyl disulfide, Dimethyl disulfide stored grain insects, true bugs, armyworms Alpha-santonin, 1,8-cineole, camphor and Artemisia armyworms α-terpineol Camellia Shikinic acid, caffeine &tannins aphids, termites and squash bugs Capsicum Capsaicin stored grain insects, weevils Dysphania Ascaridole leaf and grain feeding beetles, grain moths linalool, Juvocimene I, II, Methyl chavicol, Colorado potato beetle, aphids, various moths and Ocimum Eugenol, true bugs 4a-α,7-β,7a-α-nepetalactone, 4a-α,7-β,7a- Nepeta Colorado potato beetles, fruit flies, repels ants β-nepetalactone, and Thymol Mentha Cineole, Carvone, Caryophyllene, Menthol rodents and stored grain pests Piper Piperine, Piperitine stored grain pests, corn ear worms, bollweevils Rosmarinus Camphor, Cineole, Camphene Japanese beetles Salvia Thujone, Camphor, Humulene aphids Sambucus Sambucus nigra agglutinin sweet potato weevils Solanum Chaconine, Solanine mosquito larvae, inhibits aphids Tagetes Ocimenone, Tagetone, Alpha-terthienyl moth caterpillars, leafhoppers, aphids, true bugs Tanecetum Pyrethrum, Thujone cabbage moths Taraxacum latex Colorado potato beetle Thymus Thymol, Carvacrol moth caterpillars Lactuca latex hornworms, cabbage worms Petunia petuniasterones hornworms, cabbage worms, Colorado potato beetles Tropaeolum isothiocyanates whiteflies, leafminers www.attra.ncat.org Page 9 been found to be one of the best tools for biologi- because their phytochemicals would attract more cal production systems. It works in two ways: the of the pests. first is its aforementioned antifeedant property; A simple botanical pesticide can be prepared from the second is that it wreaks havoc on the insects’ four good-sized garlic cloves blended into one physiology. This latter effect prevents molting and quart of water. After blending, let the solution leads to sterility. So an application of neem is both preventative and curative (Schmutterer, 1995). sit for 10 to 15 minutes, then strain. Straining through cheesecloth or a fine sieve is essential Neem also has fungicidal affects and can be useful to remove the small particles that would clog a in reducing symptoms of several garden patho- sprayer. The solution should all be used as soon as gens (Govindachari et al., 1998). Leaf extracts possible; it is not meant to have a long shelf life. from the neem tree are also effective (Wondafrash et al., 2012), although a bit less effective than the One drawback of homemade botanicals is that seed extracts. In both of the previous experiments, there is no standard for efficacy. They work for when they tested various individual components however long they will work and then need to be purified from the mix, none were as effective as reapplied. It’s best to have plenty of source mate- the crude form. This is commonly the case, since rial planted around the garden and set aside for plant constituents are often synergistically active this use. When harvesting your source material, and additively effective. Neem’s cousin, the china- use the same rule as for harvesting leafy vegetables: berry tree, contains similar phytochemicals and a generally, pick less than 1/3 of the plant in order few extra meliatoxins that are harmful to mam- to give it sufficient leaf mass needed to recover. mals. However, some forms of the Chinaberry Botanical sprays can be effective and cheap. They tree are without those specific toxins, because the are truly a renewable resource that is an aid in species widely varies from one area of adaptation reducing hotspots of insect pest activity in the gar- to another. den or on the farm. Combining their use with the Pyrethrum is often used in conjunction with various companion planting methods can increase other pesticides in biological agriculture. Pyre- their effectiveness and reduce pest pressure. thrums are knock-down killers, fast acting and broad spectrum. They are effective against a range Options for System Design of pests: ants, soft-bodied insects, beetles, moths, Agronomists use the term “intercropping” to leafhoppers, spider mites, stink bugs, thrips, web- describe the spatial arrangements of compan- worms, flies, pantry pests, and mosquitoes. Pyre- ion planting systems. Intercropping systems range thrum has been used to kill insects for hundreds from mixed intercropping to large-scale strip inter- of years. On the other hand, there are quite a few cropping. Mixed intercropping is commonly seen instances of insects overcoming not only pyre- in traditional gardens where two or more crops are thrum but also synthetic versions of the pesticide. grown together without a distinct row formation. Many plants express insecticidal traits. The key Strip intercropping is designed with two or more to using them for your benefit is using them on crops grown together in distinct rows to allow for plants that are very dissimilar and thus produce mechanical crop production. No-till planting or different phytochemicals. For example, nastur- transplanting into standing cover crops can be tiums repel many pests, but they are in the Bras- considered another form of intercropping. For sica family and thus would be mostly ineffective more information on no-till planting, request the against cabbage moths or other pests of Brassicas ATTRA publication Conservation Tillage.

Page 10 Companion Planting & Botanical Pesticides: Concepts & Resources References: Ciaccia, C., E. Testani, G. Campanelli, S. Sestili, F. Leteo, F. Tittarelli, F. Riva, S. Canali, and A. Trinchera. 2015. Alves, D.S., D.F. Olivera, G.A. Carlvalho, D.A. Carlvalho, Ecological service providing crops effect on melon-weed L.P. Souza, and O. Lasmar. 2013. Selection of active plant competition and allelopathic interactions. Organic Agricul- extracts against the coffee leaf miner Leucoptera coffeella ture. Vol. 5, No. 3. p. 199-207. (Lepidoptera: Lyonetiidae) Revista Brasileira de Plantas Medicinais. Vol. 15, No. 3. Cicek, H., J.R. Thiessen Martens, K.C. Bamford, and M.H. http://dx.doi.org/10.1590/S1516-05722013000300007 Entz. 2014. Effects of grazing two green manure crop types in organic farming systems: N supply and productivity of Amarawardana, L., P. Bandara., V. Kumar, J. Pettersson, V. following grain crops. Agriculture, Ecosystems & Environ- Ninkovic, and R. Glinwood. 2007. 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Biochemical Society Transactions. Vol. 22. p. 230– mondback moth. Crop Protection. Vol. 24. p.804–813. 233. www.attra.ncat.org Page 11 Hooks, C.R., R.R. Pandey, and M.W. Johnson. 2007. Using substances. Journal of the Science of Food and Agriculture. Clovers as Living Mulches To Boost Yields, Suppress Pests, Vol. 90. p. 1210-1217. and Augment Spiders in a Broccoli Agroecosystem. UH– Martinez, R.T. 2007. An evaluation of the productivity CTAHR IP-27. of the Native American ‘Three Sisters’ agriculture system www.ctahr.hawaii.edu/oc/freepubs/pdf/IP-27.pdf in northern Wisconsin. University of Wisconsin. Stevens Jabran, K., G. Mahajan, V. Sardana, and B.S. Chauhan. Point, Wisconsin. 2015. Allelopathy for weed control in agricultural systems. http://epapers.uwsp.edu/thesis/2007/Martinez.pdf Crop Protection. Vol 72. p. 57-65. Mei, P., L. Gui, P. Wang, J. Huang, H. Long, P. Christie, Jackai, L.E.N., and S.R. Singh. 1983. Suitability of selected and L. Li. 2012. 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Vol. 19, Tagetes species: agricultural biomasses as sources of biocidal No. 2.p. 108-114.

Page 12 Companion Planting & Botanical Pesticides: Concepts & Resources Rozema J, J. van de Staaij, L.O. Björn, and M. Caldwell. Ullrich, S.D., J.S. Buyer, M.A. Cavigelli, R. Seidel, and J.R. 1997. UV-B as an environmental factor in plant life: stress Teasdale. 2011. Weed seed persistence and microbial abun- and regulation. Trends in Ecology and Evolution. Vol. 12. dance in long-term organic and conventional cropping sys- p. 22–28. tems. Weed Science: Vol. 59, No. 2. p. 202-209. Schmutterer, H., ed. 1995. The Neem Tree: Azadirachta Vernon, R.S., T. Kabaluk, and A. Behringer. 2000. Move- indica A. Juss. and Other Meliaceous Plants: Sources of ment of Agriotes obscurus (Coleoptera: Elateridae) in straw- Unique Natural Products for Integrated Pest Management, berry (Rosaceae) plantings with wheat (Gramineae) as a trap Medicine, Industry, and Other Purposes. VCH Verlagsge- crop. The Canadian Entomologist. Vol. 132. p. 231–241. sellschaft, Germany. Virk, J.S., K.S. Brar, and A.S. Sohi. 2004. Role of trap crops Schoeny A., J. Menat, A. Darsonval, F. Rouault, S. Jumel, in increasing parasitation efficiency of Trichogramma chilo- and B. Tivoli. 2008. Effect of pea canopy architecture on nis Ishii in cotton. Journal of Biological Control. Vol. 18. p. splash dispersal of Mycosphaerella pinodes conidia. Plant 61–64. Pathology. Vol. 57. p. 1073–1085. Weller, R.F., 2006. The experience of IGER Ty Gwyn. p. Schreiner, R.P. 2004. Mycorrhizas and mineral acquisition 3-17. In: Richard Weller and Andrew Jackson. Organic in grapevines. p. 49-60. In: Proceedings of the soil environ- Dairy Farming Technical Guide. Organic Centre Wales. ment and vine mineral nutrition symposium, San Diego, Aberystwyth, UK. http://orgprints.org/11090/ CA. American Society for Enology and Viticulture. Whitney, A.S. 1966. Nitrogen fixation by three tropical for- Schulz, M., A. Marocco, V. Tabaglio, F.A. Macias, and J.M. age legumes and the utilization of legume-fixed nitrogen by Molinillo. 2013. Benzoxazinoids in rye allelopathy-from their associated grasses. Herbage Abstracts. Vol. 38. p.143. discovery to application in sustainable weed control and Wondafrash, M., E. Getu, and G. Terefe. 2012. Neem, organic farming. Journal of Chemical Ecology. Vol. 39. p. Azadirachta indica (A. Juss) extracts negatively influenced 154-174. growth and development of African bollworm, Helicoverpa Shelton, A.M., and F.R. Badenes-Perez. 2006. Concepts and armigera (Hubner) (Lepidoptera: Noctuidae). Academic applications of trap cropping in pest management. Annual Journal of Entomology. Vol. 5, No. 1. p. 22- 27. Review of Entomology. Vol. 51. p. 285–308. Sherley, G. 2000. Invasive Species in the Pacific: A Tech- Further Resources: nical Review and Draft Regional Strategy. SPREP, Apia, Traditional Companion Planting Samoa. Bob Flowerdew’s Complete Book of Companion Gar- Spiers, J., F. Davies, C. He, K.M. Heinz, C.E. Bogran, and dening. 1995. By Bob Flowerdew. Kyle Cathie, London, T.W. Starman. 2008. Do insecticides affect plant growth GB. and development? Greenhouse Grower. February. p. 1-4. Carrots Love Tomatoes: Secrets of Companion Planting Tabashnik, B.E., T. Brévault and Y. Carrière. 2013. Insect for Successful Gardening, 2nd edition. 1998. By Louise resistance to Bt crops: lessons from the first billion acres. Riotte. Storey Communications, Pownal, VT. Nature Biotechnology. Vol 31. p. 510–521. Companion Planting and Insect Pest Control. 2013. By Tanga, A.A., T.F. Erenso, and B. Lemma. 2014. Effects of J.E. Parker, W.E. Snyder, G.C. Hamilton, and C. Rodri- three tree species on microclimate and soil amelioration in guez‐Saona. In: Agricultural and Biological Sciences: Weed the central rift valley of Ethiopia. Journal of Soil Science and Pest Control-Conventional and New Challenges. and Environmental Management. Vol. 5, No. 5. p. 62-71. Edited by S. Soloneski and M. Larramendy. Tavares, W.S., I. Cruz, F. Petacci, S.S. Freitas, J.E. Serrão, www.intechopen.com/books/weed-and-pest-control- and J.C. Zanuncio. 2011. Insecticide activity of piperine: conventional-and-new-challenges toxicity to eggs of Spodoptera frugiperda (Lepidoptera: Noc- Companion Plants and How To Use Them. 1966. By tuidae) and Diatraea saccharalis (Lepidoptera: Pyralidae) H. Philbrick and R. Gregg. Devin-Adair Publishers, Old and phytotoxicity on several vegetables. Journal of Medici- Greenwich, CT. nal Plants Research. Vol. 5, No. 21. p. 5301-5306. Great Garden Companions: A Companion-Planting Tillman, P.G., and B.J. Mullinix, Jr. 2004. Grain sorghum System for a Beautiful, Chemical-Free Vegetable Garden. as a trap crop for the corn earworm, Helicoverpa zea (Lepi- 1998. By Sally Jean Cunningham. Rodale Press, Emmaus, doptera: Noctuidae) in cotton. Environmental Entomology. PA. Vol. 33. p. 1371–1380. www.attra.ncat.org Page 13 How To Grow More Vegetables Than You Ever Thought Intercropping Research Possible On Less Land Than You Can Imagine, 5th edition. 1995. By John Jeavons. Ten Speed Press, Berkeley, CA. ATTRA Publications Innoculation of Legumes. By University of Hawaii Nif- Intercropping Principles and Production Practices TAL (Nitrogen Fixation by Tropical Agricultural Legumes) Farmscaping to Enhance Biological Control Center. www.attra.ncat.org www.ctahr.hawaii.edu/bnf/Downloads/Training/BNF%20 “Border effects on yields in a strip-intercropped soy- technology/Inoculation.PDF bean, corn, and wheat production system.” 1996. By T.K. J. Howard Garret’s Organic Manual. 1993. By J. Howard Iragavarapu and G.W. Randall. Journal of Production Agri- Garret. Lantana Publishing Co., Dallas, TX. culture. Vol. 9, No. 1. p. 101-107. A fine general guide on organic growing that features a Provides a nice literature review of research to that time on brief table of companion herbs and the pests they repel on intercropping, highlighting the multitude of factors causing page 48. variability in results. Raising With The Moon: The Complete Guide to Gar- Multiple Cropping. 1976. ASA Special Publication No. 27. dening and Living by the Signs of the Moon. 1993. By American Society of Agronomy, Madison, WI. Jack R. Pyle and Taylor Reese. Down Home Press, Ashe- boro, NC. “Strip intercropping for biological control.” 1993. By Joel Grossman and William Quarles. The IPM Practitioner. Contains both companion planting charts and a listing of April. p. 1–11. insect repellent plants. An excellent synopsis of intercropping. The IPM Practitio- Rodale’s Successful Organic Gardening: Companion ner, published 10 times per year, is a benefit of membership Planting. 1994. By Susan McClure and Sally Roth. Rodale in the Bio-Integral Resource Center (BIRC). Annual mem- Press, Emmaus, PA. bership for individuals costs $35. Roses Love Garlic: Companion Planting and Other Contact: Secrets of Flowers. 1998. By Louise Riotte. Storey Com- BIRC munications, Pownal, VT. P.O. Box 7414 Berkeley, CA 94707 Tel.: 510-524-2567 Beneficial Habitats ATTRA Publications Farmscaping to Enhance Biological Control Biointensive Integrated Pest Management Overview of Cover Crops and Green Manures www.attra.ncat.org

Page 14 Companion Planting & Botanical Pesticides: Concepts & Resources Appendix: Ancient Companions

By Mardi Dodson Dry field corn is divided into three categories, dent, flint, and flour corns. Dent corns are adapted best to the Southeast and Contents: the Midwest. Dent corn has a distinctive dimple-like dent on Introduction...... 15 top of the kernel when it is fully dried. A dent corn that grows Corn...... 15 well most anywhere in the United States is the Cherokee Blue Beans...... 16 and White of the Southeast. Reid’s Yellow Dent is also widely Squash...... 16 adapted. Bloody Butcher produces blood-red ears of corn on Cultivation and Planting Designs...... 17 stalks that can reach from 10 to 12 feet (Erney, 1996;, Rosen- Summary...... 20 thal, 1993). References...... 20 Flint corn grows best in the northern plains region. The kernels of flint corn do not shrink when they are dry. A popular Introduction flint corn is Indian Ornamental, with colors ranging from For centuries, many Native American tribes throughout North purple to yellow. Two other popular flint corn varieties are America have cultivated corn, beans, and squash. The term Fiesta and Little Jewels. Little Jewels is a unique, “mini” “Three Sisters” was primarily used by the Iroquois who live ornamental with four-inch-long, multi-colored ears and purple in the Northeastern United States and Canada. These crops husks (Rosenthal, 1993). were considered to be special gifts from Great Spirit and were Flour corns usually have thinner-shelled kernels filled with soft believed to be protected by the Three Sisters—spirits collectively white starch. Flour corns were developed in the arid Southwest. called the De-o-ha-ko, meaning “our sustainers” or “those who They are less likely to succeed in cooler northern regions with support us” (Eames-Sheavly, 1993). short growing seasons and in moist, humid areas where they This ancient style of companion planting has played a key role are susceptible to a fatal rust disease. Hopi Pink is a short, in the survival of all people in North America. Grown together, drought-resistant corn, with kernels that range in color from these plants are able to thrive and provide high-yield, high-qual- cranberry to light pink. This variety has plump, thin-shelled ity crops with a minimal environmental impact. Corn, beans, kernels that grind easily into fine flour. A flour corn that works and squash have a unique symbiotic relationship in a Native well in northern gardens is Mandan Bride. This variety is also American garden. Corn offers a structure for the beans to climb. drought-tolerant, with red, blue, yellow, pink, and purple spot- The beans, in turn, help to replenish the soil with nutrients. ted kernels (Rosenthal, 1993). And the large leaves of squash and pumpkin vines provide living Corn can be harvested earlier in the season when it is still mulch that conserves water and provides weed control. “green corn.” Green corn is harvested when the corn is still in the “milk” stage, when the kernels are at their sweetest and can Corn be eaten fresh. Varieties that are sweet when young are Blue Corn is considered the most important of all Native Ameri- can crops. Originating in South America and Mexico, corn The Legend of the Three Sisters was introduced during the Mississippian Period (600 A.D. to The term “Three Sisters” emerged from the Iroquois creation 1450 A.D.) to North American tribes via an intricate series of myth. It was said that the earth began when “Sky Woman” trade networks. Corn, beans, and squash combine to create a who lived in the upper world peered through a hole in the nearly perfect meal loaded with essential vitamins and min- sky and fell through to an endless sea. The animals saw her erals (Erney, 1996). In addition to its nutritional values, all coming, so they took the soil from the bottom of the sea Native American tribes that grew corn considered it a sacred and spread it onto the back of a giant turtle to provide a safe and spiritually valuable plant. place for her to land. This “Turtle Island” is now what we call North America. Varieties Sky Woman had become pregnant before she fell. When she landed, she gave birth to a daughter. When the daughter Choosing the right varieties of corn is essential to the success grew into a young woman, she also became pregnant (by of a Three Sisters garden. The tall, sturdy heirloom varieties the West wind). She died while giving birth to twin boys. Sky work best because they are most capable of supporting the Woman buried her daughter in the “new earth.” From her beans. There are a number of Native American heirloom corn grave grew three sacred plants—corn, beans, and squash. varieties to choose from. Traditionally, most of the corn grown These plants provided food for her sons, and later, for all of by Native Americans is dry field corn, which is used in flour humanity. These special gifts ensured the survival of the Iro- production. Dry field corn is harvested late in the season when quois people (Erney, 1996). the ears have dried on the stalk. www.attra.ncat.org Page 15 Table 1: Colorful Corn Varieties Can Be Variety Type Color Eaten Comments Fresh

Anasazi Flour Multi  Ancient Southwestern variety, drought-tolerant

Beasley's Red Dent Dent Red  Heirloom from Indiana Black Mexican/Iroquois Sweet Blue-Black Smaller variety from the Northeast Black Aztec Sweet Blue, Black, Purple  Originated from southern Mexico Bloody Butcher Dent Red  Northeastern United States, Virginia area Blue Clarage Dent Blue  Ohio/West Virginia Bronze-Orange Sweet Bronze-Orange  Selected by Dr. Alan Kapuler Cherokee Blue & White Dent Blue and White  Grown throughout North America Cherokee White Flour White Grows 12-15 ft. tall Fiesta Flint Multi Developed in New Hampshire Hopi Pink Flour Pink Short, drought-tolerant, Southwestern variety Hickory King Flour Yellow 12 ft. tall heirloom Indian Ornamental Flint Multi Widely grown by North American Indians Little Jewels Flint Multi 4-inch-long corn developed in New Hampshire Mandan Bride Flour Multi Originated from the Mandan tribe Mandan Red Flour Reddish-Black  Developed in Washington Oaxaca Green Dent Green Southern Mexico, makes green flour Rainbow Inca Sweet Multi  Developed by Dr. Alan Kapuler Rainbow Indian Flour Multi Developed by Dr. Alan Kapuler Texas Honey June Sweet Yellow  Heirloom, sturdy 7-8 ft. stalks Tuscadorea/Iroquois White Flour White Tall, Iroquois variety *Adapted from Amazing Maize! Cultivate Colorful Corns by Eric Rosenthal.

Clarage, Bloody Butcher, and Black Mexican/Iroquois. Flour Cranberry, a dark red bean with a meaty texture and a nutty corns are usually not eaten in the green corn stage. Two excep- chestnut-like flavor, also performs well in the South and in the tions to this rule are Anasazi and Mandan Red (Rosenthal, Northeast. Cornfield, unrelated to Genuine Cornfield, does 1993). See Table 1. well in the Pacific Northwest because it matures before the fall rains come. A favorite in the arid Southwest is Hopi Purple, Beans a purple bean with black crescent-moon stripes (Erney, 1996). Beans provide a high-quality protein food source that combines well nutritionally with corn. Beans also play a valuable Squash role in the Three Sisters garden. Through a symbiotic relation- Growing low to the ground, squash and pumpkin serve as living ship with rhizobium bacteria, beans help to take nitrogen from mulch. The large leaves block out much of the sunlight, thus the air and convert it into a usable form for next year’s crop. reducing weed seed germination. Allelopathy may be an additional factor in weed suppression (Fujiyoshi, 1998). (Allelopathy Varieties refers to chemical secretions from a plant which have adverse Pole beans are best adapted to directly climb the corn stalk as or phytotoxic effects on some weed species.) opposed to sending runners across the ground. The Scarlet Runner variety is a popular heirloom pole bean that is famous Varieties for its large clusters of bright red flowers. Genuine Cornfield Most any variety of squash will work in a Three Sisters gar- consistently produces in the heat of Southern summers. True den. In addition to the contemporary hybrid varieties, there

Page 16 Companion Planting & Botanical Pesticides: Concepts & Resources are still some traditional varieties available. In the North-east, Figure 1. Circular Wampanoag Garden the Penobscot and Abenaki still grow Long Pie (a.k.a. Indian or Golden Oblong) pumpkin. This pumpkin looks like a fat zucchini with the texture of a pumpkin. It has a long storage life and usually doesn’t turn orange until after it is harvested. A disease-resistant variety suited for the Southeast is the Connecticut Field. This very vigorous Native American heirloom yields large, bright orange pumpkins. Mayo Blusher is a very sweet, pale gray pumpkin that blushes pink when ripe. Cushaw is a gourd-like squash that has been grown in the Southwest by the Pueblo Indians for storage containers since pre-Columbian times. Other varieties of squash also grow well in the Southwest depending on the amount of moisture available (Erney, 1996). Cultivation and Planting Designs Planting designs and cultivation practices vary according to climatic region. Garden styles were developed mainly out of practical considerations, such as moisture availability, climate, and the length of the growing season. The Wampanoag garden style works well east of the Mississippi. Hidatsa gardens Drawing by Mardi Dodson. Concept taken from Native American were developed to thrive in the climate of the northern Plains, Gardening by Michael J. Caduto and Joseph Bruchac. while the Zuni waffle garden was designed to conserve water in the arid Southwestern climate. When the mounds are ready, plant four corn seeds about 6 Wampanoag Three Sisters Garden inches apart and 3 inches deep in the top of each mound. Once the corn has grown to a height of 4 inches or more, plant It was the Wampanoag gardens that enabled the early settlers four beans seeds halfway down the slopes on the sides of each of Jamestown to survive and thrive in the New World. Squanto mound (see Figure 2). Allow the bean vines to entwine them- was a Wampanoag who “taught the newcomers to plant maize selves around the cornstalks for support. The bean vines may be in little hills and fertilize each mound with an alewife, a species pruned if they get too aggressive (Caduto and Burchac, 1996). of fish” (Gabarino and Sasso, 1994). With this efficient and intensive gardening style, each family could sustain their needs Squash seedlings are planted at the same time as the beans. on about one acre of land. Many of the tribes of the Northeast, Construct rounded mounds 3 inches high and about 1 foot including the Iroquois, used the Wampanoag garden design. across at the base. The squash mounds are staggered between the mounds of corn and beans (see Figure 1). Planted without plowing or tilling, the traditional Wampanoag garden includes corn, beans, squash, and sunflowers. The corn and beans are planted in mounds, with squash planted between Figure 2: Wampanoag Corn & Bean Mound the mounds. The sunflowers are planted along the north edge of the garden, so that they do not cast a shadow on the other crops (see Figure 1). When the sunflowers have bloomed and the squash and beans have flowered, the Wampanoag Three Sisters garden becomes a stunning cluster of red, yellow, and white flowers against a textured backdrop of shimmering greens. First, the raised corn and bean mounds must be constructed. These small mounds are laid out in rows with 4 feet between the centers of the mounds (see Figure 1). Each mound is about four inches high, with a wide base (about 18 inches in diameter) that narrows to a flattened top (about 10 inches across). To conserve moisture, a depression with a lip may be formed at the top of each mound (Caduto and Burchac, 1996). Corn is planted 6 inches apart in the flat top of the mound. Beans are planted halfway down the slopes on the sides of the mound. Draw- The finished mounds have a remarkable resemblance to min- ing by Mardi Dodson. Concept taken from Native American Garden- iature moon craters. ing by Michael J. Caduto and Joseph Bruchac. www.attra.ncat.org Page 17 Figure 3: Wampanoag Squash Mound squash mounds are located along the east, west, and south edges of the garden in alignment with the rows of beans (see Figure 4). Squash seedlings are usually transplanted when they are about four inches tall and have put on their first set of true leaves (about two weeks after the corn is planted). To protect them from the heavy spring rains, four seedlings are planted on the sides of the mound in sets of two, 12 inches apart (see Figure 5) (Caduto and Burchac, 1996). In the Hidatsa garden, there are usually four corn mounds per row of corn. Note that the rows of corn are in alignment but are staggered in comparison to the beans (see Figure 4). Hidatsa corn mounds are constructed in the same way as the Wampanoag corn and beans mound. The differences are that Drawing by Mardi Dodson. Concept taken from Native American Gardening by Michael J. Caduto and Joseph Bruchac only corn is planted in these mounds and eight seeds, instead of four, are planted in the top of each mound (see Figure 6). Figure 4: Hidatsa Garden Design Traditionally, four seedlings are planted in the top of each mound. The seedlings are arranged to represent each of the four sacred directions (see Figure 3). Both winter and summer varieties are planted, including pumpkins, acorn squash, and summer crookneck squash (Caduto and Burchac, 1996). Sunflower seeds are planted at the same time as the corn. The smaller-flowering common sunflower, Helianthus annus, is traditionally grown in a Wampanoag Three Sisters garden. The sunflower mounds are located at the north edge of the garden (see Figure 1). The mounds are spaced about three feet apart from center, with three seeds planted (one seed per hole) atop each mound. The sunflowers seeds are traditionally harvested after the first frost (Caduto and Burchac, 1996).

Hidatsa Gardens In the northern plains, the Hidatsa, Mandan, and Arikara peoples gardened along the floodplain of the Missouri River in what is now called North Dakota. Most of the tribes in this region used the Hidatsa garden design (see Figure 4). Hidatsa gardens are designed to have alternating, staggered rows of corn Drawing by Mardi Dodson. Concept taken from Native American and beans, with sunflowers growing along the north edge of Gardening by Michael J. Caduto and Joseph Bruchac. the garden. Squash is planted after every fourth row of corn and beans and around the east, south, and west edges of the Figure 5: Hidatsa Squash Mound garden (Caduto and Burchac, 1996). Sunflowers are planted as soon as the threat of frost has passed. As in the Wampanoag garden, three sunflower seeds are planted in small mounds three feet apart along the north edge of the garden. The Hidatsa garden differs from the Wampanoag garden when it comes to seed arrangement—all three seeds are planted in one hole. Hidatsa varieties of sunflower produce black, red, white, and striped seeds (Caduto and Burchac, 1996). Plant squash indoors in peat pots or seed flats when the sunflowers are planted in the garden. Before planting in the garden, prepare the squash mounds (about 15 inches across at the Drawing by Mardi Dodson. Concept taken from Native American base), with four feet between the centers of the mounds. The Gardening by Michael J. Caduto and Joseph Bruchac.

Page 18 Companion Planting & Botanical Pesticides: Concepts & Resources Figure 6: Hidatsa Bean Mound together to plant beans. The first person made six holes in the south-facing slope of the bean mound. This is done in one swift motion by thrusting both hands into the soil with the thumb and first two fingers extended to make two sets of holes spaced six inches apart (see Figure 7). The second person fol- lows behind and plants one seed in each hole. A total of six seeds are planted in each bean mound (Wilson, 1917).

Zuni Waffle Garden The Zuni live in the Four Corners area of the Southwestern United States. This arid climate at altitudes over 7,000 feet makes gardening a special challenge. The Wampanoag and Bean seeds are planted on the south-facing slope of the mound. Hidatsa garden designs use raised mounds to keep the root One seed is planted per hole, with a total of six seeds planted in systems from being waterlogged. In contrast, the focus of this each mound. Drawing by Mardi Dodson. Concept taken from Native American Gardening by Michael J. Caduto and Joseph Bruchac. garden is water conservation. The waffles are about 12 feet by 12 feet. Each individual square is indented and surrounded by Figure 7: Hidatsa Corn Mound a high rim. In each square, a single crop or combinations of crops may be planted (see Figure 8). This garden design will work anywhere in the country where dry summer conditions are experienced. Traditionally, the crops are planted intensively with five to eight corn seeds in each hole to create clumps of corn similar to those in the Hidatsa garden. Corn seeds are planted four to eight inches deep in light sandy soils and about four inches deep or less in heavier clay soil. Beans and squash have the same planting depths and spacing requirements as corn (Tala- vaya Center, no date). The same number of beans (four to eight seeds) are planted around each clump of corn, one seed per hole. Only one or two squash plantings (four to eight seeds in

Figure 8: Zuni Waffle Garden

In a Hidatsa garden, eight seeds are planted atop each mound. Drawing by Mardi Dodson. Concept taken from Native American Gardening by Michael J. Caduto and Joseph Bruchac.

Growing corn together in bunches offers extra support and protection from wind and rain damage. Hidatsa flint corn is planted in May in North Dakota when the leaves of the Gooseberry shrubs have emerged and fully formed. Corn is planted a week or two after the sunflowers have been planted. This flint corn is a semiarid variety with a growing season of about 70 days. It is advisable to research which corn variety works best for your zone and climatic conditions (Wilson, 1917). Beans are planted at the same time as corn. In a Hidatsa garden, beans are planted separately from the corn in their own mounds. The bean mounds are located between the rows of corn in a staggered, alternating pattern (see Figure 4). The mounds are rounded ovals, about four inches tall by seven inches wide by 14 inches long. Traditionally, two people worked Drawing and design by Mardi Dodson. www.attra.ncat.org Page 19 each hole) are added to each waffle (see Figure 8) (Rosenthal, References 1993). As with the other two designs, sunflowers may also be Buchanan, Carol. 1997. Brother Crow, Sister Corn. Ten planted along the edges of the Zuni Waffle garden. Helian- Speed Press, Berkeley, California. thus maximilianii, a small sunflower with flower heads about three inches wide, is most commonly grown in the Southwest Caduto, Michael J. and Burchac, Joseph. 1996. Native (Buchanan, 1997). American Gardening. Fulcrum Publishing, Golden, Colo- rado. p. 70-93. Summary Eames-Sheavly, Marcia. 1993. The Three Sisters: Exploring Native American tribes of North America have made enor- an Iroquois Garden. Cornell University Cooperative Exten- mous contributions to the foods we eat today. The dynamic sion. p. 7. trio known as the Three Sisters not only thrive when they are Erney, Diana. 1996. Long live the Three Sisters. Organic planted together, they offer a well-balanced, nutritious meal. Gardening. November. p. 37-40. Over the centuries, many plant varieties and gardening styles were developed for each major climatic region. The Wampa- Fujiyoshi, Phillip. 1998. Mechanisms of Weed Suppression noag (Northeast and South), Hidatsa (Plains), and Zuni waffle By Squash (Cucurbita spp.) Intercropped in Corn (Zea mays garden (Southwest) offer a range of gardening styles to accom- L.). Disserta- tion University of California Santa Cruz. modate most growing conditions found in North America. Gabarino, Merwin S. and Sasso, Robert F. 1994. Native Corn, beans, and squash have a unique symbiotic relationship American Heritage. Waveland Press, Prospect Heights, Illi- in a Native American garden. Corn offers a structure for the nois. p. 308. beans to climb. The beans, in turn, help to replenish the soil Rosenthal, Eric. 1993. Amazing maize! Cultivate colorful with nutrients. And the large leaves of squash and pumpkin corns. Organic Gardening. March. p. 30-35. vines provide living mulch that conserves water and provides Talavaya Center. No date. Talavaya Seed and Planting Man- weed control. This ancient style of companion planting has ual. Espanola, New Mexico. p. 5-11. played a key role in the survival of all people in North America. Grown together these crops are able to thrive and provide high- Wilson, Gilbert L. 1917. Agriculture of the Hidatsa Indians. yield, high-quality crops with a minimal environmental impact. Minnesota Historical Society Press, St. Paul, Minnesota.

Companion Planting & Botanical Pesticides: Concepts & Resources By George Kuepper & Mardi Dodson July 2001 Updated April 2016 by Justin Duncan Tracy Mumma, Editor • Robyn Metzger, Production This publication is available on the Web at: www.attra.ncat.org IP125 Slot 71 Version 041816

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